Detector arrays are made up of a plurality of detector elements that are operable to convert energy, in the form of electromagnetic radiation (EMR), to electrons. Different types of detector arrays operate at different bands of wavelengths. For example, charge-coupled device (CCD) detector arrays and complimentary metal-oxide-semiconductor (CMOS) detector arrays typically operate in the band of visible light. A focal plane array typically operates in an infrared (IR) band of wavelengths. Because each detector element converts any EMR within a particular band of wavelengths to electrons (in the form of current or voltage differences), the detector element by itself cannot identify the receipt of EMR of a particular wavelength or a subset of wavelengths within the band of wavelengths in which the detector element operates.
A color filter, such as a Bayer filter, may be used to identify specific bands of wavelengths received by a detector element. For example, in the context of a point-and-shoot consumer camera, a green filter element may be placed upstream of a detector element to filter out all EMR outside of a green wavelength band. Thus, any EMR received by the respective detector element must be in the green wavelength band. Similarly, a red filter element may filter out all EMR outside of a red band, and a blue filter element may filter out all EMR outside of a blue band. Unfortunately, the approach of filtering out all EMR except a particular band of desired energy reduces the overall energy received by a detector array by as much as 80%. Post-processing algorithms may then be used to construct an image of the scene by determining the intensity and the colors of the scene based only on the energy received that was filtered through the respective filter elements and detected by the corresponding detector elements. Moreover, because each detector element detects only one color, points from the scene are typically blurred to spread energy over a plurality of pixels in each color, resulting in a loss of spatial resolution.
Detector arrays are used in a wide variety of different applications, including consumer applications, forensics, healthcare, industrial, security, and military applications. In some contexts, the spectral information received from a scene by a detector array is used to infer information about the scene, such as the presence of particular objects in the scene. The more energy captured by the detector elements, and the higher the spatial resolution, the greater the likelihood is of identifying objects in the scene. Thus, a methodology that operates by filtering out 80% of the energy received from a scene and that reduces spatial resolution is not an ideal methodology for analyzing the content of a scene.